Transmission



H. C. SNOW TRANSMISSION July 8, 1941.

Filed July 28, 1938 G Sheets-Sheet 1 [ave/27%;?

Harte/"2" C $0041 y 1941- H. c. SNOW 2,248,133

' TRANSMISSION Filed July 28, 1938 6 Sheets-Sheet 2 y 1941- H. c. SNOW 2,248,133

TRANSMISSION Filed July 28, 1938 6 Sheets-Sheet 3 wnq B r7n0 mm, W/

4Z1 l ||Z llllllll l 6 Sheets-Shet 4 H. c. SNOW wmnsmssxon Filed July 2a, 1938 July 8, 1941.

July 8, 1941. H. c. SNOW TRANSMISSION Filed July 28, 1958 6 Sheets-Sheet 5 y 8. 1941- H. c. sNow 2,248,133

' TRANSMISSION Filed July 28, 1938 s Sheets-Sheet 6 Patented July 8, 1941 TRANSMISSION Herbert 0. Snow, Auburn, Ind., assignor of onefourth to Clarence H. Dooley, Rock Island, 111., one-fourth to H. Keith Dooley, Los Angeles, C'alif., and one-fourth to Delmar D. Dooley,

Rock Island, Ill.

Application July 28, 1938, Serial No. 221,724

29 Claims.

This invention relates to transmissions, especially to those adapted for automotive use, and is concerned more particularly with transmissions of the type having mechanism for auto matically changing the driving ratio.

The object and general nature of this invention is to provide a transmission unit having a torque controlled mechanism for changing the ratio automatically in response to torque conditions but which is, nevertheless, subject to a manual control by the operator, making it 'possible to lock the unit in'the desired ratio or to manually pre-select a ratio in which the parts will be locked when that ratio is selectediby the operation of the automatic mechanism.

A further feature of this invention is the provision of a unit affording two different ratios, preferably controlled by the transmitted torque, in which when the driving connection in one ratio is interrupted, preparatory to shifting into the other ratio, a connection is maintained which while insufficient to drive the vehicle is suflicient to insure a positive and complete shift unto the other ratio. This is an important fea-' ture of the invention, especially when incorporated in a torque responsive device, in that it insures a positive and complete shift from one ratio to another without any danger' of the mechanism remaining temporarily isolated in an intermediate position resulting in hunting or in ratcheting or chattering of the gears, and in which no torque would be transmitted.

. vention is the provision of an overdrive or an underdrive unit for transmissions and the like in which the ratios available are automatically controlled according to the torque transmitted, and a further feature of this invention is the protailed description, taken in conjunction with the accompanying drawings.

In the drawings:

Figure 1 is a longitudinal vertical section taken through a transmission overdrive unit in which the principles of the present invention have been embodied;

Figure 2 is a fragmentary view showing certain of the parts of the torque responsive mechanism in elevation;

Figure 3 is a fragmentary section at a reduced torque-responsive sleeve in shifting from its direct drive position to its over-drive position, with the manual control unlocked;

Figures 8 to 10 illustrate the same movement of the torque-responsive sleeve, from direct drive vision of an automatic transmission in which one a or more torque responsive units may be incorporated, each affording an automatic control of two different ratios.

These and other objects and advantages of my invention will be apparent to those skilled in the art after a consideration of the following deto overdrive, but with the manual lock in a position pre-selecting the retention or locking of the sleeve in its overdrive position;

Figure 11 shows in section the means for retaining the torque-responsive sleeve against rotation on the driving member but accommodating its generally axial movement;

Figures 12 to Marc fragmentary perspective views, showing the form of clutch teeth employed on the shiftable torque-responsive sleeve and the associated clutch members to prevent jamming;

Figure 15 is a reduced section taken through a modified. form-of the present invention in which the feature of torque responsive control is replaced by a manual control;

Figure 16 is a longitudinal vertical section of automatic transmission embodying the features of the present invention;

Figure 17 is a sectional view showing an overdrive unit adapted for installation at the rear axle, with the torque-responsivev unit arranged rearwardly of the planetary unit; and

Figure 18 is a view similar to Figure 17 but with the parts reversed in order to provide a reduction unit instead of an overdrive unit.

Referring now more particularly to Figures 1 and 2, in which the principles of the present invention have been embodied in an overdrive unit 3 which is adapted to be secured at the rear end of a conventional transmission and driven from the driven shaft of the latter, the reference numeral I indicates a conventional transmission The overdrive unit is indicated in its entirety by the reference numeral I and includes a housing or casing having a flange |2 by which it may be secured, either directly to the transmission casing wall 2 in a suitable manner, or to an adapter plate 1, as by cap screws l3. The mechanism enclosed within the overdrive casing includes, generally, a torque responsive device l5 and an epicyclic gear change unit I6. A driven shaft I1 is supported by suitable bearings It! in the rear wall l9 of the casing II and at its forward end the shaft I1 is piloted, as at 2|, in a recess 22 formed in the rear portion of a driving member indicated in its entirety by the reference numeral 23; The member 23 includes a hub 24 that is splined to receive the end 5 of the transmission shaft 3, which constitutes a driving shaft for the overdrive mechanism, and the rear portion of the member 23 extends radially outwardly in the form of a drum or flange 25, the peripheral surface of which is provided with helical splines 26 (Figure 2) which are interrupted by a pair of peripherally extending axially spaced grooves 21 and 28-disposed about the driving member 23. Engaging the helical splines 26 of the latter is an axially shiftable torque-responsive sleeve 30, which is provided on its interionsurface with two sets of splines, as at 3| and 32, separated by an interrupted portion. The splines 3| are disposed at the forward end of the sleeve 30 and are also helical so as to mesh with the splines 26 on the driving member 23. The rear set of splines 32 are axially straight and are not helical or spiral. A cap screw 33 bears against a washer 34 which engages the splines on the driving member 23 for the purpose of holding the latter fixed to the rear end of the shaft 3. The forward end of the member 23 holds the inner race of the bearing means 4-up against a shoulder on the shaft 3;

The sleeve 30 is shiftable generally axially relative to the driving member 23 and is yieldingly held in either position by a plunger 35 which is disposed in a recess 36 formed in the driving member 23. The plunger 35 is biased for outward movement by a spring 31. plunger 35 is shown, it will be understood that as many plungers may be employed as desired. The outer end of each plunger is beveled to seat into either one of two peripheral grooves 39 and 4| which are formed in the splines 3|, as best shownin Figure 1. Axial shifting movement of the sleeve 39 is limited in one direction by a spring ring 42 which seats in a groove 43 formed in the spline teeth 3|, and movement of the sleeve 30 in the other direction is limited by theengagement of a shoulder 44 with the rear fade of the member 23, as shown in Figure 1.

When the sleeve 30 is shifted from one position to another it is necessary at first, to exert appre- 'ciable force in order to depress the plunger 35 against the action of the spring 31, but once the bias of the plungers 35 has beenovercome no further exertion of force is necessary, other than While only one I enough toovercome the slight frictional resistplungers 35 enter the other grpove 4|. The same action is present when the sleeve 39 is to be shifted back from the position shown in Figure 2. It will be understood that if only one or a limited number of plungers 35 are employed, the grooves 39 and 4| may, if desired, take the form of a notch or notches in certain of the splines 3|, since it is not absolutely necessary that all of the splines 3| have the grooves 39 and 4| formed therein. However, for convenience of manufacture and assembly I prefer to cut the grooves 39, 4| as continuous through all of the splines 3|.

The rear internalsplines 32 on the shiftable sleeve 30 are, as described above, in the form of axially directed straight teeth. Adjacent its forward end the driven shaft ll carries a collar 46 which is mounted on the splined portion 41 in fixed nonrotatable relation. The collar 66 has interior splines interengaging with the splines 41, and at the forward end of the shaft H. a spring ring 49 seats in a groove formed in the shaft and serves to hold the collar 46 in position on the shaft H. The peripherally outer. portion of the collar 46 is flanged, as at 50, and is provided with a plurality of clutch teeth 5|, the form of which is best shown in Figure 12 and will be referred to later.

Surrounding the rear portion of the driven shaft I1 is an epicyclic gear unit indicated in its entirety by the reference numeral 60. The epicyclic gear unit is preferably of the overdrive type and includes a ring gear 6| having a hub 62 which is fastened in nonrotatable relation to the rear end of the shaft preferably by beingsplined and mounted on splines 63- at the rear end of the shaft ll. The hub 62 of the ring gear 6| is also formed, as at 64, to receive the inner race 65in which the bearings I8 are carried, the

outer race 66 being fixed to the housing wall IQ of the overdrive casing H in any suitable manner, as by a spring ring 68. The ring gear member 60 is held against forward movement on the a shaft I! by a ring or collar 69 disposed against a shoulder on the shaft l1 at the inner ends of the splines 63. A plurality of planet gears mesh with the ring gear 6| and with a sun gear '12 having teeth 13 which are extended into a stationary yoke I4 that is secured in fixed relaprises a member 8| journaled for rotation by suitable bearings 82, preferably of the needle type, on the driven shaft H. The member 9| includes a forwardly extending hub section 64 and a flanged section 65, the latter being apertured to receive'a plurality of tubular pivots 81 upon which the planet gears 1| are mounted for rotation, as by bearings 88. Preferably, the pins 81 are hollow and are provided with one or more oil openings 9| to facilitate lubrication of the bearings 88. Each pivot pin 81 is also provided with an opening 92 to receive a locklngpin 93 which is received in an aperture 94 in a ring 96 that forms a part of the planet gear carrier or cage 19. Asheet metal shell 91 is disposed above the ring 96 and has portions 98 clamped about a shoulder 99 formed on the ring 96 for the purpose of holding the pins 93 in position. The flange and the ring 96 are also apertured to receive, rivets Illl on which suitable spacing sleeves I02 are mounted. Each rivet and its associated sleeve is disposed between adjacent planet gears.

Since the ring gear 6| is constantly connected to the rear end of the driven shaft I1 and the sun gear is constantly held against rotation, it will be seen that rotation of the gear carrier 19 will act through the planet gears and react against the sun gear to drive the ring gear at a speed greater than the speed of the gear carrier 19.

A collar or clutch member I01 is fixed, as by being splined, keyed, or otherwise, to the forward end of the planet gear carrier member BI.

The member I01 is similar to the member 46 in that it is provided with a plurality of teeth I08 (Figure 13), the members 46 and I01 being axially aligned but with their toothed portions and I08 separated by a space. An anti-friction thrust ring H0 is disposed between the members 46 and I01 and serves to hold the collar I01 up against a snap ring III. A rear thrust ring H2 is placed between the member 8| and the member 62. A cap screw 33a and a washer 34a clamp the universal joint part H3 and speedometer gear II4- against the race 65 on'the rear end of the shaft I1, and this holds the ring gear memany relative axial movement between the parts of the epicyclic gear unit.

The collar members 46 and I01 have recessed sections H6 and H1 to provide space accommodating a pair of overrunning clutch springs H9 and I20, best shown in Figure 2. The clutch spring H9 has an end I2I turned axially and engaged in a notch I22 formed in the member 46 adjacent the base of the flanged section 50. The other end of the spring H9 is free. The other spring I20 is formed with a similarly bent end I25 which is received in a notch I26 formed in the other collar member I01, and similarly the other end of the spring. I20 is free. A pair of sleeves I3 Ia and I3Ib surround the clutch springs II9 and I20, the internal diameter of the sleeves I3Ia. and I3Ib and the external diameters of the clutch springs IIS and I20 being such that,the parts are in close fitting relationship. The sleeves I3Ia and I3Ib carry, respectively, sets of straight splines or teeth I32 and I33 (Figures 1 and 2) one or the other set of which are in constant mesh with the internal splines or teeth 32 on the shiftable sleeve 30, but never both except during an intermediate position during a shift, as will be explained below. The sleeve sections are spaced apart by an anti-friction ring' I34. The clutch teeth SI and I08 are of the same pitch as the teeth I32 and I33, whereby in one position the shiftable sleeve 30, which it will be remembered is at all times in driving connection with the drive member 23 and the shaft 3, connects one of the sleeves I3Ia or I3Ib'with-one of the clutch collars, and in the other position the sleeve 30 connects the other of the sleeve members I3Ia or I3Ib with the other clutch collar.

. ber 60 against the ring 69, thereby preventing the teeth 32 on the shiftable sleeve 30, as best shown in Figures 12, 13 and 14, so as to facilitate the ready and positive engagement of the shiftable sleeve with the associated clutch collars when the sleeve is shifted, either automatically or manually. Figure 12 is a perspective view of one of the clutch teeth 5I on the clutch collar 46. As indicated, the ends I35 and I36 of each tooth are in radial planes, but the end I36 of each tooth is chamfered, preferably at as indicated at I31. This end of each tooth is also cut away to form tapered edges I38 and "I39 which lie in planes that extend generally radially but which are disposed substantially at right angles to each other. The end I36 of each tooth is therefore particularly formed to enter into mesh with a companion toothed part. The clutchteeth I08 are vof generally the same configuration as just described and, as best shown in Figure 13, have ends I360. which are narrow and are flanked by tapered edges I38a and I39a, each tooth I08 being beveled, as at I31a. The end of each tooth I08 opposite the end I36a is, unlike the tooth shown in Figure 12, formed with a backward bevel, indicated at I40 in Figures 1, 2, and 13. The width of the end sections I36 and I360 are somewhat exaggerated in Figures 12 and 13 in order to show the form of teeth clearly. The teeth 32 on the torque-responsive shiftable sleeve 30 are formed with edges or ends that come to a point so as to facilitate the movement of the associated shiftable sleeve into engagement with the associated clutch teeth 5| and I08. Referring now to Figure 14, it will be noted that opposite ends of each .tooth are formed by surfaces -I42 and I43 which lie in generally radial planes, but which extend substantially at right angles to each other, thereby forming at each end .of the tooth an entering edge... The outer ends of the teeth I32 and I33 on the sleeves I3I.a and I3") preferably are formed as just described in connection with Figure 12.

By virtue of this construction, whenever the shiftable sleeve 30 is moved toward engagement with one or the other of the associated clutch members, the sleeve teeth readily enter between the clutch teeth without abutting or becoming jammed. This is an important feature of the present invention, particularly in connection with the automatic torque responsive shift control. I

The operation of the mechanism so far described is as follows, referring particularly to Figures 5 to 10, inclusive:

connected at all times, but arranged for axial The clutch spring H9 is so arranged that the movement relative to, the driving member 23, when the parts are arranged as indicated in Figure 1, it will be seen that the drive is transmitted from the members 3 and 23 through the shiftable sleeve 30 to the clutch collar 46, since the member 30 is in its forwardmost position. Thus, the shafts 3 and I1 are adapted to rotate together, at a direct or one-to-one ratio. The

splines 26 and ill are so angled with respectto the direction of rotation of the parts that the torque transmitted from one shaft to the other exerts a component of force tending to move the sleeve 30 forwardly until the shoulder 44 engages through the members 23 and 39 to the collar 46 which is fixed'directly to the shaft I1. In this position of the sleeve 39 the spring biased plunger 35 engages in the groove 39 and serves 39 rearwardly, due to the aforesaid angular relation of the teeth 6 and 3|. This movement of the sleeve 39 is, owever, opposed by the resistance offered by spring biased plungers 35, but

if the torque transmitted is suflicient, the resistance of the plungers 35 may be overcome, with the result that the springs 31 yield and the plungers 35 move inwardly out of the groove 39, thus permitting the sleeve 39 to shift rearwardly. When the plunger or plungers 35 have been forced entirely out ofthe groove 39, which occurs before the teeth 32 and 5| become disengaged, there is no further appreciable resistance to the rearward movement of the sleeve 39 so that the latter moves until the teeth 32 are fully disengaged from the teeth 5| on thedriven shaft clutch member 45, as shown in Figure 6.

At this stage the shiftable sleeve 39 is in an intermediate position, that is, its teeth 32 are out of engagement withthe clutch member 46 but are not in engagement with the teeth I98-on the clutch collar I91, ,and since the plunger 35 is entirely out of the groove 39 and is riding on the flat interior portion of sleeve 39 between the grooves 39 and 4|, the sleeve 39 is quite free to move axially in either direction. This does not mean, however, that the sleeve 39 is entirely disconnected from either of the shafts 3 or I1. Under the condition of operation assumed, where the :driven shaft I1 is driving the shaft 3 and associated parts in the direction of the arrow in Figure 1, and remembering that the member I91 is being driven at a reduced rate through the epicyclic gear unit 69 from the shaft IT, as soon as the teeth 32 are out of engagement with the clutch member 46, the shaft 3 and sleeve 39 continue, to decelerate until their speed is equal to the speed at which the clutch member I91 and gear carrier or cage 19 are driven by the shaft I1 through the epicyclic gear-unit. As soonas the speed of the shaft 3, sleeve 39, and members I3Ia and I3Ib has dropped down to the speed of the clutch member I91, the overrunning clutch spring I29 takes hold of the sleeve section I3Ib and then the reversed torque begins to be transmitted from the engine back to the shaft I1 through the epicyclic gear unit, the clutch member I91, the clutch spring I29, and the member I3Ib to the'sl'eeve ,39 which, as mentioned above,

is free to move axially without resistance. Therefore, instead of expanding its force to drive the motor through the sleeve 39, member 23 and shaft 3, the reversed torque acts immediately to resiune the axially rearward movement of the sleeve 39 until the groove 4| reaches the plungers 35. The plungers then snap into position in the groove 4|, actually assisting the completion of the axially rearward movement of the sleeve 39 and bringing the parts to the positions shown in Figures 2 and 7. Thus, the overrunning clutch spring 129 need be strong enough only to shift the relatively free sleeve 39 and is not capable of actually driving the motor. 'This rearward movement of the member 39 just described has carried the teeth 32 in the positive engagement with the teeth I 98 on the clutch collar I91, which is fixed and serves as a driving member for the gear cage 19, and the meshing of the teeth is facilitated by the particular form of the teeth (Figures 13 and 14). If now, the motor is accelerated so that the shaft 3 again becomes the driving part of the system, the drive is transmitted through the members 23, 39 and I91 to the epicyclic gear unit, and from there to the driven shaft I1, thereby driving the latter at an increased rate as compared with direct drive.

Thus, when the parts are arranged for direct drive between the shafts 3 and I1 (Figure 1), a reversal of torque of suflicient magniture will immediately and automatically shift the member 39 rearwardly and will establish the parts in position for overdrive. This action is automatic upon the occurrence of a reversal of torque, but it will be remembered that by simply lifting his footoff the accelerator, the operator of an automobile can secure a reversal of torque whenever desired, so that the movement of the parts into their overdrive position is entirely within the control of the operator. It will be noted that the shift is made more or less independently of the relative speeds of the parts, since it is a torque reversal and not the relative speed of one part with respect to the other that effects the shift.

It will be remembered that the inclination of the spiral splines on the interengaged driving member 23 and shiftable sleeve 39 is such that in normal operation the torque transmitted tends at all times to move the shiftable sleeve 39 forwardly. Thus, when the parts are arranged in an overdrive, as in Figures 2 and '7, the torque transmitted tends to shift the sleeve 39 forwardly into direct drive position (Figures 1 and 5). However, this movement is initially resisted by the spring biased plunger or plungers 35, with the result that the parts remain in their overdrive position so long as the torque component arising by virtue of the spiral splines does not exceed that required to cause the sleeve 39 to force the plungers inwardly out of the groove 39. The amount of torque required to cause the sleeve member 39 to shift forwardly into directv drive position may be adjusted or controlled, first, by the springs 31, second, by the inclination of the side walls of the grooves 39 and 4| which need not be the same, and/or third, by the weight of the plungers 35. Since the parts are normally revolving, the efiect of centrifugal force on the plungers 35 is to augment the springs 31 in holding them in the groove, 39 or 4|, in which they are disposed. Thus, the faster the automobile is being driven, the greater will be the torque required to shift the sleeve 39, and this applies in both the shift into direct as well as the shift into overdrive.

-When the torque exerted in normal forward driving with the sleeve 39 in its overdrive position'becomes suflicient to overcome the plungers 35 and forcethem out of the groove 4|, the shiftable sleeve 39 moves out of engagement with the clutch teeth I98 of the clutch member I 91 and into an intermediate position, as in Figure 9,

in which there is no appreciable resistance to axial movement, of the sleeve. Then when the speed of the shaft 3 and sleeve 39 has increased 'as at I61, and is'bolted or otherwise secured to ber I01, as mentioned above, the overrunning spring Stakes hold of the member I3Ia and the torque exerted against the sleeve 30 shifts the latter forwardly and completes the forward movement of the sleeve 30 until the teeth 32 are carried into engagement with the teeth I (Figure 8), which brings the shoulder 44 up against the face of the member 23, at which time the plunger 35 snaps into engagement with the groove 39. Thus again the plungers 35 aid in completing the movement of the sleeve 30.

By virtue of this construction, therefore, whenever the torque exerted exceeds a predetermined value, depending partly upon the speed of rotation of the parts, the unit automatically shifts to the lower speed, namely, direct drive. While this shift, also, is automatic, it is nevertheless entirely possible for the operator of the automobile to secure a shift from overdrive into direct drive at practically any time desired, merely by suddenly accelerating the engine so as to exert the torque required to overcome the bias of the plungers 35. So far as I am aware, it is broadly new to utilize the driving torque for shifting into a low ratio and to utilize the coasting or reversal torque for shifting into a high ratio, with overrunning clutch means not subject to the stresses involved either in driving the car .or in turning the motor over against its own compression upon deceleration, but operative only to automatically complete the torque responsive shift into the other ratio after the positive connection in one ratio has been released. Preferably, the overrunning clutch springs Ma and I20 are made of material such as bronze, that has a low coefiicient of fric tion with the sleeves I3Ia and I3| b, so that the springs will slip slightly under load, thus insuring that the clutch teeth will always engage.

Under certain conditions it may be desirable to provide means for locking the unit in one or both positions as desired so as to temporarily overrule any torque-controlled call for a shift into a higher or a lower ratio. Referring again to Figure 2, the member 23 is provided with a recess I5I in which a plunger I52 is mounted for reciprocatory movement. The plunger I52 is hollow and at its lower end is bored to receive a screw I 54 that is threaded into the member23 to maintain the parts in position. A spring I55 surrounds the screw I54 and at its upper e d bears against the head of the screw and at 5 lower end bears against the inner end of the plunger I52. When the unit is arranged for overdrive (Figure 2) and the speed of the parts is sufficiently great, centrifugal action causes the plunger I52 to move outwardly to its dotted line position, into an opening I51 formed in the shiftable sleeve 30. As long as the plunger I52 is in its dotted lineposition, the member 30 will be prevented from shifting, even though there should occur a temporary reversal of the torque, thereby holding the parts in their overdrive position so long as the speed is above a given value.

If desired, a manuall controlled type of lock for controlling the movements of the shiftable sleeve 30 may be provided and can, for example, be controlled by a suitable member mounted on the dash of the automobile or some other point. Referring now to Figures 1 to 4, a sleeve I60 surrounds the shiftable sleeve 30 and is provided with a radially outwardly extending flange I6I. The casing II is formed with an extended section I64 (Figure 3) which is milled, as at I65, to receive-a supporting sleeve I66 which is flanged,

- shaft I10, the inner-end of which extends into the interior of the casing II and has an arm I1I fixed thereto. A yoke I12 is pivoted, as at I13, to the arm "I and has spaced apart sections I16 and I11 (Figure 2) arranged to receive the flange I-6I. The arm I1I has a plurality of recesses I19 (Figure 3) into any one of which a spring pressed ball I8I carried by the flange I61 of the sleeve I60 is adapted to enter to hold the outer sleeve I60 in an intermediate position or in either of its end positions.

An arm I84 is fixed by clamping bolt I85 to the outer end of the rock shaft I10, and the outer end of the arm I84 is apertured, as at I86, to receive one end of an operating rod I81 which extends through the opening, I86 in the arm I84 and is movable therein. A pair of springs I89 and I90 aredisposed about the rod I81 and are placed on opposite sides of the arm I84. Suitable abutment. washers I92 and I93 are carried by the rod I81 to receive the reaction of the springs I89 and I90, the washers being held in place by cotter pins I94 and I95. Thus, whenever a pull is exerted on the rod I81, the arm I84 rocks the arm [1! in one direction 'or the other to shift the position of the locking sleeve I60. The yielding of the springs I89 and I90 permits some relative movement between the arm I84 and the rod I81, as will be referred to below. The operating rod I81 may extend to or be controlled by means mounted on the instrument panel or some other convenient place easily accessible to the driver of the automobile. Preferably, however, the control is arranged so that the unit I0 is locked in direct position when the transmission I is in neutral or any speed other than direct.

Normally the locking, sleeve I60 is rotatable with the driving member 23, and to this end the sleeve I60 is formed with a boss I96 (Figure 11) which is threaded to receive a cap screw l91 The inner end of the cap screw I91 extends through a slot I98 formed in the shiftable sleeve 30 and into a notch I99 in the central portion of one of the splines 26 on the driving hub member 23. The slot I98 is formed at the same angle as the spiral splines 26 and 3| and acts through the pin I91 to keep the sleeve I60 from. rotating rela- I tive to the driving member 23.

As best shown in Figure 1, the torque-responsive shiftable sleeve 30 is provided with an aperture MI in which aball 202 is placed. The inner surface of the locking sleeve I60 adjacent the opening 20! is provided with an elongated recess or groove 203. It will be remembered that the sleeve 30 is shifted under the control of the transmitted torque from one position, that shown in Figure 1,

for example, to another position, that shown in Figure 2, for example. The grooves 21 and 28 are formed to receive the ball 202, which is carried by the sleeve 30, in either of the final positions of the sleeve 30. The groove or slot 203 is deep enough to receive the ball 202 when the movement of the sleeve 30 relative to the driving member 23 causes the ball 202 to. be forced out of one of the grooves 21and 28, provided the locking sleeve I60 is in its intermediate position, as shown in Figures 1 and 2. Looking at Figure 1,

- it will be seen that if the ball 202 is prevented from moving out of the recess or groove .21 in the.

member 23, the shiftable sleeve 30 will be prevented from moving, regardless of the backward torque that may be transmitted from the shaft I1 through the sleeve 30 to the driving shaft 3. One way of preventing theball 202 from leaving (Figure 7) back to the groove or recess 21 is to shift the locking sleeve I to the right (dotted lines, Figure .5) so that the cylindrical portion I00a of the sleeve I00 overlies the ball 202 and prevents its movement out of the groove 21. If the sleeve 30 were in its overdrive position, with the ball 202 lying in the of torque transmitted.

The operation of the locking sleeve and associated parts and the manner in which they function to preseiect the locking of either of the ratios desired, will be clear from Figures to 10, inclusive. In Figures 5, 6 and 7, the locking sleeve I00 is shown in its intermediate position, which unlocks both of the available ratios for control by the amount of torque, the shiftable sleeve 30 moving axially from one position to another as determined by the torque requirements. In Figure 5, the shiftable sleeve 30 is shown in its forward position,.in which the drive is transmitted directly from the driving shaft 3 to the driven shaft I1,

1 this being the position also indicated in Figure 1.

With the locking sleeve I60 retained in its intermediate position as shown in Figure 5, when the sleeve 30 is shifted rearwardly under the eflect .of reversed torque, the first movement of the sleeve 30, which disengages the teeth 32 from the j clutch teeth 5I, also moves .the locking ball 202 out of the notch or groove 21 and into the groove 203 in the locking sleeve I00. As the speed of the engine drops down to that of the collar I01 of the epicyclic gear unit and the reversed torque is transmitted momentarily through the overrunning clutch spring I20 from the member I01 to the member IS"), the continued torque will cause the sleeve 30 to resume its rearward movement until the ring 42 is brought into engagee ment with the forward face of the member 23 and the teeth 32 engaged with the clutch teeth I08 on the overdrive clutch member I01. It will be observed from Figures 5 to '7, that the notch or groove 203 in the locking member I00 accommo- 'dates the outward movement of the locking ball 202 (Figure 6) during its movement from the groove 21 to the groove 28. Similarly, the movement of the ball 202' will be accommodated when the sleeve 30 is moved from an overdrive position its direct drive position (Figure 5) 1 If it is desired tolock' the sleeve 30 in its direct drive position, as is shown in Figure 5, all that it is necessary to do is to move thesleeve I60 to the right into the dotted line position (Figure 5),

:which carries the cylindrical portion 100a of the sleeve I00 over the ball 202,. thereby effectively preventing the latter from leavingthe notch 21,

and since the ball 202 cannot leave the notch 21 the sleeve 30 cannot be shifted. If, on the other hand, it is desired to lock the sleeve 30 in an overdrive position, as is shown in Figure '1, in

that case all that it.is necessary to do is to move the sleeve I00 forwardly into the dotted line po- .'sition so asto bring the cylindrical portion I6,0b

of the slee .e I00 over the ball 202, locking the latter in the notch 28, and thereby preventing the sleeve30 from shifting out of its overdrive position. The movement. of the locking sleeve I in either direction out of its intermediate position {may be accomplished by moving the. rod I81 (Figure 4) in one direction or the other, as described above.

, The locking mechanism described above is also capable of being preselected; that is, when the transmission unit: is in, say, direct drive the operator can arrange the unit so as to have the mechanism locked in overdrive if and when it is shifted into its overdrive position. According to the present invention all that it is necessary to do to preselect a locked overdrive relation is to shift the sleeve I60 forwardly from its neutral or intermediate position (full lines, Figures 5 to 7) into a forward position (dotted lines in Figure '1, and full lines in Figures 8, 9 and 10). The dotted line position of the sleeve I00 in Figure 8 is in its intermediate position. With the locking sleeve I00 in a position arranged to lock the unit in overdrive hen the torque-responsive sleeve 30 is in direc drive, the relation of the parts are as indicated in full lines in Figure 8. Assume now that there occurs a reversed torque sufficient to shift the sleeve 30 toward its overdrive position. The position of the groove 203 is such that-the ball 202 may move out of the slot 21 and into the groove 203, but from Figure 9 it will be noted that in this position the ball 202 engages the right hand margin of the groove 203, speed of the engine is reduced to correspond to overdrive relations, the resumption of reversed torque, as the resistance is transmitted back through the member I3Ib from the collar I01 through the clutch spring I20 to the sleeve 30, continues the rearward movement of thesleeve 30. Since, as stated, the ball 202 engages the margin of the groove 203' but cannot enter the groove or recess 28, this continued rearward movement of the sleeve 30 carries with it the locking sleeve I00 substantially to the dotted line position shown in Figure 9, this action being accommodated by the spring I90 (Figure 4) yielding to permit the sleeve I00 temporarily to follow the sleeve 30, until the ball 202 can enter the notch 28. As soon as the ball 202 is over the groove 28, the springI90 acts against the arm I84 and the shaft I10 to return the sleeve I00 to the position shown in Figure 10 with the section I00b overlying the ball 202 which is the normally [locked position for overdrive, as indicated 11 dotted lines in Figure '1. After the sleeve 00 moves over the ball 202 the sleeve is effectively locked in overdrive and is no lo'ngerresponsiv'e to torque, for the reason that the ball 202 cannot leave the groove 28 and hence the sleeve 30 cannot be moved forwardly.

From the above description'it will beapparent that the same action takes place when the sleeve I60 is moved into its direct locked position when the sleeve 30 is in an overdrive unit.

It will thus be apparent from the above description that the movement of the actuating rod I81 out of a position permitting automatic operation into a direct locked position or an overdrive locked; position will'immediately lock the shiftable sleeve 30 against movement if thesleeve- The two sleeve sections I3 Ia and I3Ib, with the anti 'friction ring I34 between them, are independently rotatable and are so arranged that Then as the 'car in reverse.

when the shiftable sleeve 30 is in either one position or the other, one of the sleeve sections has its teeth engaged by the sleeve 30 while the other sleeve section is free of the sleeve 30. For example, when the unit is arranged for direct drive (Figures 1 and 5), the teeth I32 on the sleeve section I3Ia are engaged by the teeth 32 on the sleeve 30, while the'other sleeve section I3Ib is free to idle since its teeth I33 are not in engagement with the teeth on the sleeve 30. In overdrive (Figures 2 and 7), the sleeve section I3Ib is engaged with the sleeve 30 while the other sleeve section I3Ia is free to idle. This particular arrangement of the separately rotatable sleeve sections I3Ia and I3Ib alternately engaged with the shiftable sleeve 30 is provided to accommodate driving the car in reverse and permitting the car to move backwardly, it being remembered' that the unit I is disposed at the rear of the transmission and hence the parts of the unit I0 are subjected to both right hand and left hand rotation. I

Assuming, by way of illustration, that the shiftable sleeve 30 is in its direct drive position (Figures 1 and 5) and that the transmission I is engaged in reverse and the main clutch connected. The shaft 3 will then be driven in a direction op.- posite to that indicated by the arrow in Figure 1 and this rearward or left hand rotation will be transmitted through the members 23 and 30 to the members 46 and I3Ia. It will be remembered that in the right hand rotation of the parts, as indicated by the arrow in Figure 1, the sleeve section I3Ib can overrun the member I01. This means that in the reverse or left hand direction sleeve against shifting while in reverse. In this event, the shift-locking control part I81 could be separated from the transmission gear shift and constructed and arranged to permit automatic operation into either a direct locked position or an overdrive locked position at any time desired, and entirely regardless of whether or not the transmission unit is at that time in one or the other of its available ratios, except reverse.

Although the shaft 3 has been described above as constituting the driving shaft for the unit I0 and the shaft H the driven shaft, it will be'obvious that this relation may be reversed if desired; that is, the shaft I1 may become the driving shaft and the shaft 3 or a part attached to the member 23 in lieu thereof may become the driven shaftv In that case, the unit becomes a reduction .unit and torque in the forward or right hand direction will tend to shift the sleeve 30 into its direct drive position, engaging the member 46, while torque reversal will tend to shift the sleeve 30 into what would be, under the conditions assumed, an underdrive or speed the member I01 overruns the sleeve section I3Ib. 1

direct drive position, the sleeve section I3Ib is free of the sleeve 30 and remains stationary or merely idles with the member I01 when the car is driven or is moved in reverse.

Reverse drive is accommodated in a similar manner when the clutch sleeve 30 isin its overdrive position (Figures 2 and '7). In this position of the parts a reverse or left hand rotation, as in reverse drive or in backward movement of the car, the part 46 is connected to the driven shaft I1 and will be rotated in a reverse or left hand direction at a greater speed than the mem ber. I01 which is connected to the driven shaft I! through the planetary gear unit. In this direction the member 46 acts through the overrunning clutch spring I I9 to drive the sleeve section I3Ia, but since this part is free of the shiftable sleeve 30, no interference is experienced.

During the transition period when the shiftable sleeve 30 is in an intermediate position it engages both of the sleeve sections I3Ia and I3Ib. When the parts are in this position. reverse drive cannot be accommodated, and if attempted the overrunning clutch parts would become jammed and the wheels of the vehicle locked. Hence, as pointed out above, preferably the sleeve 30 is locked in its direct position in all selected gear ratios, in-- eluding reverse, in the transmission except direct drive. If desired/of course, means controlled by the selection off reverse drive in the transmission could be provided for automatically holding the Hence, with the sleeve 30 in its reduction position.

The present invention is not necessarily limited to providing two different ratios and torque responsive means for automatically selecting one or the other ratio. Figure 15 illustrates an arrangement embodying a transmission unit substantially the same as that described above except that the unit is not'responsive to the torque transmitted.

Referring now to Figure 15 in which parts that are identical with those described above have been indicated by the same reference numeral and in which for purposes of clarity portions of the epicyclic gear unit 60 has been omitted, the reference numeral 223 indicates a driving member that is fixed to the rear end of a drivin shaft 3a, as by being mounted on splines 225 formed in the rear end of the shaft 3a. The driving member 223, like the member 23 described above, is secured in place on the shaft 3a by a cap screw 33 and a ring washer 34 which bears against the end of the member 23 and forces it upagainst the inner race of the bearing. unit 4a which journals the shaft 3afor rotation in a supporting part 2a. The flange or hub section 230 of the member 223 is provided with a plurality of straight splines 23I, instead of being spiral or helical as in Figures 1 and 2. and the splines 23I mesh with corresponding splines 232 formed on a shiftable sleeve 233, the latter having a flange 234 which is adapted to be engaged by the shift fork I12 shown in Figure 3. The rear end of the shiftable sleeve 233 is provided with another set of straight splines 236 which mesh with the teeth I32 on a sleeve member I3I and are adapted to mesh with the clutch teeth SI and I08, optionally. Preferably, the ends of the teeth 5|, I08, 236 and 231 are formed in the manner shown inl igures 12, 13 and 14 to facilitate shifting from one ratio to theother. The other parts of the transmission unit shown in Figure 15 are substantially the same as those shown in Figure l, the position of the sleeve 23I being under the control of the rock shaft I10 and arm I84 and serving to determine whether the drive is transmitted directly to'the shaft I! through the clutch collar 46 or through the collar I01 and epicyclic gear unit 60.

l The shiftable sleeve 233 is held yieldinglyinone position or the other by means of a spring pressed ball 240 which seats in a recess I in tional transmissions.

the hub section 238 and the drive member 233 and is urged outwardly by a spring 242. The ball 248 is adapted to enter either of two peripheral grooves 244 and 245 which are formed in Z the splines 232. The shifting movement of the/sleeve 233 is limited in one direction by the engagement of the teeth 236 with the face of thesction 238, or by the engagement of a spring ring 246 which is snapped in agroove formed in the forward end of the sleeve 233.

The unit shown in Figure 15 is not responsive to the torque transmitted, but is adapted to be manually controlled at all times. Thus, the movement of therod 181 in one direction or the other acts through one or the other of the associated springs shifts the sleeve 233 from one position to another. Moreover, like the torque responsive form of the invention described above.

the overrunning clutch springs 119 and 120 serve to synchronize the clutch parts and facilitate the shifting of the sleeve 233. The sleeve -131, unlike the sleeve-sections 131a and 131b, is one integral part, and hence the unit shown in Figure 15 cannot accommodate reverse rotation and for automotive work should therefore be disposed forward of the transmission.

It will be noted that the principles of the present invention as embodied in the transmission units described aboveh ve been set forth as adapted for units which are in the nature of attaclgnents or auxiliary accessories for conven- However, the present invention is equally applicable to the construction of transmission which do not have auxiliary units pletely automatic, as may be desired.

Referring now to Figure .16, the reference numeral 215 indicates in its entirety a transmission having a gear box 216 and driving and driven shafts 211 and 218 journaled therein. For convenience of illustration I have shown a'trans-i mission which* is more or less of the conventional type, in so far as it has three speeds forward and reverse, but provided with a unit indicated in its entirety by the reference numeral 280 which renders the transmission automaticas regards the selection of second or third speeds according to torque and speed requirements.

The transmission 215 includes a lay shaft 282 upon which a tubular countershaft 283 is mounted for rotation, as .by bearings 284 and 2.85 The countershaft 283 includes a gear- 281 which.

shift fork 295 of any suitable construction. .Rearwa'rdly of the gear 292 is a compound gearunit 291 which includes two gear sections 288 and 288. The gear cluster'291 is'held against movement bya pair of spring rings 381 and 382.

The driven shaft 218 includes a rear splined portion 385 on which a sliding "gear 306 is mounted. The gear 386 is controlled by a shift fork 381 and may be shifted into mesh with the gear section 298 or with a reverse idler (not shown) that is driven from the gear section- 299. When the gears 298 and 306 are in mesh, the transmission is arranged for first or low speed, as in conventional practice. Forward of the splined section 385 the driven shaft 218-is formed to receive a bushing 388 upon which a gear 318 is mounted for-rotation, and forward of the gear 3 I 8 .the shaft 218 is splined, as at 311, the forward reduced end 312 of the shaft 218 being supported by pilot bearings 313 in a recess 314 formed in the rear end of the driving shaft 211.

According to the principlesof the present invention, when the gear 282 is shifted forwardly into mesh with the gear 310 the operation of the automatic torque responsive unit 280 is such, that the drive from the driving shaft 211 to the driven shaft 218 is transmitted either directly or through the pairs of gears 288, 281 and 292, 318 to provide two different ratios which are automatically selected according to torque conditions. The unit 280 by which this automatic operation is secured will now be described.

A clutch section 320 is formed on or carried by the driving shaft 211 and has clutch teeth 321 which preferably are of the same form shown in Figures 1 and 13.- A second clutch section 323 is formed on or carried by the gear 318 and has a plurality of clutch teeth 324 substantially like those shown in Figures 1 and 14 described above. The splined-section 31 I of, the driven shaft 218 receives adriven hub member 328 which is fixed against rotation and axial displacement in the section 311 in any suitable manner. The driven member 328 is formed with spiral or helical splines 328 which are interrupted by a pair of axially spaced grooves 331 and 332. A shiftable sleeve member 3351s provided with a radially inwardly directed central flange section 336 which is formed with spiral or helical spline teeth 338 in constant mesh with the-splines 328 on the driven member 328. The spline teeth 338 do'not extend entirely acrossthe flange section 336 but terminate short thereof, forming, in effect; two grooves 338 and 348 for the reception of a ball plunger 341 which is carried in a recess 342 formed in the driven member 328 and: biased for outward movement by a spring 343;

The shiftable sleeve 335 is provided with two sets 344 and 345 of straight spline teeth with which a pair of clutching members 348 and 349 are in con'st nt engagement, the members 348 and 348 ha ng teeth 351 and 352 with which the teeth 344 and 345 are in engagement. The central portion 336 of thegshiftable sleeve 335 receives a locking plunger 355 and a lockingsleeve 356'surrounds the shiftable sleeve 335 and is formed with a groove 351 in which the outer end of the locking plunger 355 is disposed when the sleeve 335 is in an intermediate'position, as shown in Figure 16, in passing frompne position to another. The sleeve 335 is limited in its shifting movement by engagement of the central section 336 with one or the other of the members 348 and 349; The locking sleeve 356 may be controlled manually by any suitable means, such as the construction indicated in Figures 3 and 4 and-described above.

The members 328 and 323 correspond func- 1 tionally to the clutch collars 46 and 181 described section 323.

,one end of, the clutch spring 364 being anchored to the member 328. Another overrunning clutch spring 365 is disposed between the members 318 and 348, one end of the spring 365 being anchored to the clutch section 323. The clutch spring 364 is so wound that the clutch section 328 can overrun the member 3 48 in the driving direction, but the latter C nnot overrun the section 328 in that direction. Similarly, the

member 349 can overrun the clutch section 323 in the driving direction, as indicated by the arrow in Figure 16, but the section '323 cannot overrun the member 349 and hence will drive the latter in the driving direction.

The operation of the transmission 215 is Substantially as follows: i

Low and reverse may be selected in the usual manner by shifting the gear .386 forwardly or rearwardly, as by the shift fork 381. After the car has been driven in low and it is desired to proceed to a higher speed, the gear- 292 is shifted forwardly on the countersha-ft 283 into mesh with the gear 3"! journaled on the driven shaft 21.8. From this point on, the control of the ratio at which the shaft 218 is driven is dependent upon torque conditions in substantially the same manner as'the unit shown in Figure 1 and described above.

The parts are represented in Figure .16 as in a transitory position intermediate a "position in which the shiftable sleeve 335 is moving from a position engaging one of the clutch sections 328 and 323 to a position engaging the other. As-

suming that the automobile has been driven under conditions requiring more torque than it is desired or possible to exert when the shafts 21.1 and 288 are connected directly together, and further assuming that the amount of torque exerted between the shiftable sleeve 335 and the hub member 328 has been suflicient' to force the spring pressed balls 341 inwardly against the springs 343, which permits the parts to take the position shown in Figure 16, in this position the clutch teeth 344 are out of engagement with the teeth 32! and acceleration of the engine will cause the clutch section 328 to overrun the member 348 andthe member 349 to overrun the gear 3H1 until the gear 3l8 rotates at the same speed as the member 349. When this occurs the gear 3", which cannot overrun the member 349, begins to drive the latter through the spring 365. At this time, however, the sleeve 335 is freely shiftable so that the instant any torque is exerted, the force is expended, not in driving the car, but in causing the sleeve 335 to continue its rearward shifting movement until the teeth 345 engage the clutch teeth 324 on the clutch section 323 and the spring biased ball 3 drops into the groove 339, whereupon a positive drive in second speed is effected;

"When it is desired to go into direct or high speed, the operatordecelerates the engine and the reversal of torque acts through the helical splines to shift. the sleeve 335 forwardly, forcing the-ball 341 out of the groove 339, until theteeth 344 engage the clutch teeth 32l and the ball 34l drops into the other groove 348, ii the manner described in detail in connection with Figures 1 and 2. As will be apparent, the weight of the balls or plungers,v the' angle of the groove side walls, and the rate of rotation control the shift from a high 'ratio'to a lower ratio in response to increased torque, and the shift to the other, or lowerfratio is likewise controlled. While I have. shown the side walls of the grooves associated with the shift controlling balls or plungers as being-substantially the same angle, with the consequence that about the same amount of torque, although in opposite directions, will bring about a shift' in ratio, it will be understood that these angles and the other factors may be varied as desired." Also, .while in Figure 16 I have shown only one torque responsive unit, this invention 'comprehends transmissions with two or more torque-responsive units to provide an automatic control of as many ratios as desired. The units associated with the lower ratios would be adjusted to be responsive to higher torques than the higher ratios. For example, the unit shown in Figures 1 and 2 may be connected to be driven by the shaft 218 of Figure 16, and in that case any one of four ratios would be selected automatically, and theunit 15 would be made responsive to a lower range of torques than the unit 288, since in such a combination the unit 288 should remain in its high speed position throughout the shifting range of the unit I5.

In the transmission of Figure 16 the sleeve members 348 and 349 are separate parts, similar to the sleeve sections Bio and l3lb described above in connection with Figure 1, but these members are not separately rotatable since they are in .constant connection with the slidable sleeve 335. The overrunning clutch springs 384 and385 in this form therefore cannot accommodate the reverse rotation of the shafts 211 and 218. This is, however, an advantage. It will be noted that the reverse gearing in this form is disposed rearwardly of the unit 288, and therefore the unit is never subjected to being driven in reverse. Hence, the unit 288 in its present form will serve as meanspreventing backward movement of the car whenever the gears 3H) and 292 are in mesh. If these gears are out of mesh, then backward movement of the car, irrespective of whether or not reverse gear is selected in the transmission, is accommodated.

Assuming that the gears 292 and 3! are in V mesh, the manner in which the unit 288 serves as a fno-back feature is as follows:

It will be remembered that for right hand or forward rotation, in the direction of the arrow shown in Figure 16, the part 320 can overrun the part 348, and. the part 349, which rotates at all times with the part 348, can overrun the part 310, the clutch springs 364 and 365 being arranged to accommodate'this action.. However, in the reverse or left handrotation, opposite to the arrow shown in Figure 16, the member 348 can overrun the member 320, and the member 323 can overrunthe member 349. Also, the member 328 can drive the member 348 and the member 349 can drive the member 323. Thus, if the gear 292 is in mesh with the gear 3 I 8, and a backward movement of the car tends to cause. a reverse rotation of the shaft 218, the part 320, which is driven faster than the 'part' 323 will tend to drive the member 348, and with it the member 349.- How ever, the member 349 tends to drive the part 323, but this part is forced to rotate slower than the part 320 due to the transmission gearing, and as a result, the parts will lock and prevent reverse rotation. As stated, this occurs only when the gear 292 meshes with the gear 318, and therefore. the unit 280 serves to prevent the car from rolling backward when the transmission is in second 'or high, depending onthe position of the sleeve 335.

The units described above havebeen designed for inclusion in or attachment to-an automobile transmission, preferably at the rear end thereof, but itis not to be considered that the species of this invention as so fardescribed are limited to installations ofthis character. torque responsive and planetary gear units may be arranged to be carried by the rear axle of an automoble, just forward of the driving pinion. A

properly constructed unit embodying this invention is not heavy and when installed in the .rear

For example, the

axle construction of an automobile does not add any objectionable amount of unsprung weight to includes a sleeve 402 in which a pinion shaft 403 is disposed. The pinion 404 meshes with a ring 'gear 405 in the usual manner, and the shaft 403 is supported in the proper position by roller bearings 401 and 408, there being a spacer 408 between the inner races of the bearings. A nut H is threaded onto a screw threaded portion 4 of the shaft 403 for the purpose of clamping the inner races andthe spacer 408 on the shaft 403.

The forward portion of the sleeve 402 is flanged, 'as at 2, and receives a collar 3 which forms a part of or is secured to a casing 4l4. Preferably, the collar 413 has a flange 5 which is apertured to-receive cap screws 6 that secure the collar 413 to the casing 414. The latter encloses planetary gear and overdrive units indicated in their entirety by the reference numerals 1 and 4| 8, respectively. The forward end of the casing H4 is closed by a plate 420 which is flanged at 421 and has an interior toothed secasbya member 462 on'the flange 465. The hub 463 is formed with a tooth clutch section 411 and an axially extending flange 412 about which an overrunning clutch spring 413 is disposed. Also secured on the splined portion 440 of the propeller shaft is a hub 415 which is also formed with a toothedclutch section 416 and a flange 411 about which a second overrunning clutch spring 418 is disposed. Preferably, the overrunning clutch springs 413 and 418 are similar to or identical with the clutch springs H9 and I described above.

The forward end of the pinion shaft 403 is splined and receives a driven hub member 480 which is ecured thereto in any suitable manner, in, 4!". The member 4801s provided with spiral splines. 482 and circumferential grooves 483 and 484 and is substantially the same w construction as the member 23 described above in *are substantially .identical with the corresponding parts shown in Figure 1 and described'above,

tion 422 which will be referred to later; The

propeller shaft is indicated at 423 and is disposed.

in a propeller shaft housing 424 that is secured by cap screws 425 to the forward end of the casing H4. The flan'ge 421 of the plate 420 is provided, with holes through which the cap screws 425 extend, whereby when the latter. are

tightened the plate 420 is secured 'flrmly and propeller shaft 423 extends rearwardly almost entirely through the casing M4 and is connected by a pilot bearing 43l to the forward end of the pinion shaft 403 in coaxial relation.

' The rear end of the propeller shaft 423 is splined, as at 440 and is shouldered, as at 44! to receive a ring 442. The planetary gear cage of the unit 4| 1 is indicated in its entirety by the and hence the same reference numerals have been applied. A speedometer drive gear 486 is mounted rearwardly of the units M1 and M8 and between the member 480 and the lock nut 4| 0. The locking sleeve I60 is preferably controlled in the same manner described above in connection with Figures 1 to 10. v

The operation of the form of the invention shown in Figure 1'1 is substantially the same as dwcribed above in connection with Figure 1.

The unit-shown in Figure 17 is also an overdrive unit, although the position 'of the planetary gear and torque responsive units have, in Figure 17, been reversed as compared with the arrangement shown in Figure 1. Thus, it will be apparent that the present invention is not dependent upon any particular a ngement of the torque responsive and planetary gear units and, further, that either end may be the driving or driven end, asdesired.

In operation, the propeller shaft 423 is driven in the direction ofthe arrow shown in Figure 1'7,

and the spiral splines 482 and the corresponding I splines 3| on the shiftable sleeve member 30 /are arranged that driving torque in a right hand reference numeral 445 and includes a member 446 having a splined hub 441 disposed in driving engagement on the splines 440 of the propeller shaft 423. The member 445 is flanged, as at 448, and apertured to receive the tubular pins 45| upon which the planet gears 452 are journaled for rotation. A ring 453 receives the ends of the pins 45l'.opposite the ends carried by-the' flange 448,

the ring 453 thus forming a part of theplanet sun gear 456 which is supported by the member 1 420 in any suitable manner. Preferably, the endsj of the teeth of the sun gear are reduced, as at 451, and received in the splines of the section 422. -i

A spring ring 458 is carried by one endof the sun gear and serves to-hold the shouldered sections of the teeth up against the side ofthe section 423 opposite which the spring ring 458 is p sed. f

The ring gear of the unit 4" is indicated at 45l and comprises a gear section 462 and a. hub section 463, the latter being joumaled for rotation on the hub 441 by suitable antifriction bearings. 464. The outer flangesection 465 of the member 468 is formed with teeth that receive the reduced ends 461 of the teeth 468 of the ring gear member 462. A spring ring 468 serves to hold the 5*. the sleeve 30 and the members I 3la' and l3lb unor forward direction tends to.shift the sleeve 30 rearwardly so-that the teeth 32. on the sleeve 30 engage the toothed clutchsectionaflli, thereby providing for a direct drive between the shafts 423 and 403. Shifting movement of the sleeve 30 is resisted by the spring pressed plunger 35 described above in connection with Figure 1. Upon the occurrence of a torque reversal, as by closing the throttle of the motor, the sleeve 30 is shifted forwardly until the teeth 32 clear the. toothed section 416. The overrunning clutch springs 413 and 418 are so arranged that-the part 463 can overrun the sleeve section l3la and the sleeve section |3lb can overrun the member 415. Thus, in the intermediate position of the shiftable sleeve 30, where; both of the sleeve sections Mia and I3Ib are connected togetherthrough the sleeve 30, the momentum of the car will drive l3la to drive the part 463 establishes suflicient force to continue the forward movement of the shiftable sleeve 30 until the teeth 32 thereof engage the toothed section 4" on the member 463, thus connecting the parts for overdrive. The motor can then be accelerated and will drive the car at a high speed in overdrive. However, if the torque-exerted should increase beyond a predetermined amount, the sleeve 30 will be shifted automatically back to its direct' drive position, substantially as described above in connection with Figure 1.

The construction shown in Figure 17 will accommodate a reverse drive in substantially the same manner as described above in connection with Figure 1, since in either the direct or the overdrive position of the shiftable sleeve 30, one or the otherof the overrunning clutch members l3la and 1311; is free to idle in either direction relative to the associated parts.

The form of the invention shown in Figure 18 embodies substantially the same parts shown in Figure 17 except that different forms of propeller pinion shafts are accommodated, and the parts, although substantially identical in the majority of instances, have been arranged to provide a reduction unit instead of an overdrive unit as in Figure 17. Parts that are identical with the construction in Figures 1 and 17, have been identified by the same reference numerals.

In Figure 18, the forward end of the pinion shaft 403a is extended through the unit and is piloted by hearing means 43m in a driving mem- 1 her 501 which has a splined connection at the rear end of the propeller shaft 423a. The driving member 501 has a recessed section receiving the inner race of the bearing means 423, and the outer drive or flange portion of the member 501 is provided with left hand spiral splines 502 which engage corresponding splines 503 formed on the-interior of the shiftable sleeve 30. The sun gear 456 of the planetary unit 1 is held in stationary relation by an interiorly splined section 422a which is formed integral with the forward portion of the collar 4l3a.

In operation, 'driving torque in the forward or right hand direction, as indicated by the arrow in Figure 18, acts through the splines 502 and 563 tending to shift the sleeve 30 rearwardly into engagement with the toothed section 411 on the hub 463 of the ring gear member 461a, and a reeversal of the torque tends to shift the sleeve 30 forwardly into connection with'the toothed section 416 formed on the member 415 that is fastened directly to the forward end of the pinion shaft 4.311. In Figure 18 the member 46la is shown with the hub and ring gear proper as formed integrally, but they may be formed separately as indicated in Figure 1'7, if desired. In the construction shown in Figure 18,'the overrunning clutch springs 413 and 418 are so arranged that, in the forward or right hand direction as indicated by the arrow, the part 463 can overrun the sleeve section l3 la and the sleeve section I3 lb can oven-1m the part 415. Thus, when the parts are arranged as shown in Figure 18, that is, for direct drive, the rotation of the gear cage 4'45 drives the ring gear member 461a faster than the rotation' of. the pinion shaft 403a and the part 41! carried thereby. Hence, the part 463 over-runs the sleeve section l3la, both when the shif-table sleeve ll is in its directldrive position and when it is inan intermediateposition in the process of shifting from direct to underdrive.

The shift from directto underdrive occurs when an excessive amount of torque is exerted between the'member ill and the sleeve 30, and as soon as the teeth 32 on the sleeve 33 disengage 463. At this moment the torque exerted acts to complete the rearward movement of the shiftable sleeve 30 until the teeth 32 come into engagement with the toothed section 41 I whereupon t'he'drive to the rear axle is resumed but now it is transmitted through the unit 1 at a reduced rate.

In both Figures 17 and 18 movement of the shiftable sleeve 30 in response to the torque exerted is or may be controlled by the locking sleeve 160 in the same manner as described above in connection with Figure 1, and if desired the same or similar arrangement mentioned above in connection withFigure 1 for positively holding the 'shiftable sleeve 30 in one or the other of its positions during reverse drive may be provided.

It will be observed that by virtue of applicants particular arrangement of the overrunning clutch means, there is always a definite ratio between the rates of rotation of the driving and the driven parts that cannot be exceeded. For example, in Figure 1, since the part l3la drives the part 46 (which is secured directly to the driven shaft l1) it will be seen that the driving shaft 3 cannot rotate faster than the shaft 11. Likewise, since the part l3lb overruns the part I01 in a forward direction and the part I01 therefore will drive the part l3lb in the forward direction through the clutch spring I20 when the power on the drive shaft 3 ceases, it will be seen that the drive shaft 3 cannot rotate slower than the part 101 which, by virtue of the overdrive unit 60, always rotates slower than the driven shaft I1. The same relations exist in the form of the invention shown in Figure 18 in which the driving shaft 423a cannot rotate faster than the driving part 463 of-the planetary gear unit 4" or slower than the part 415 which is fixed directly to the driven shaft 403a. By virtue of the underdrive unitfl46la, the part 463 always rotates faster than the shaft 403a. In Figures 16 and 17, the driven shaft cannot rotate faster than the faster rotating part of the two driving members nor slower than the slower driving member. That is to say, in Figure 16. the driven shaft 218 maynot run faster than through the gear 292 from'the counter shaft 283.

In Figure 17 the driven shaft 403 cannot run .any faster than the part 463 or slower than the part 415. By virtue of the planetary gear unit 46l, the part 463 always rotates faster than the part 415 which is fixed directly to the driving shaft 423.

While I have shown and described above the preferred means in which the principles of the present invention have been embodied, it is to be understood that my invention is not to be limited to the specific details shown and described above, but that. in fact, widely different means may be employed in the practice of the broader aspects of my invention.

What I claim, therefore, and desire to secure by Letters Patent is: r

1. In a transmiss on, shiftable means prov ding two different ratios, torque responsive mechanism comprising overrun'ning slipping clu ch able mem partmay rotate with respect to thedriving part,

spaced apart members connected to transmit the drive from one part to the other at difierent ratios through said means, a shiftable part operatively connected with the driving'part and engageable with either of said members, a pair of overrunning slipping clutches connecting said shiftable part with said members when the shiftable part is out of engagement with both of them, and manual means for locking said shiitable part in either of its positions.

cal splines separate from said annular grooves for establishing a shit-table torque responsive connection between said member and said sleeve, said sleeve having an opening therein, a locking part disposed insaid opening and movable with said sleeve from a position wherein the locking part can enter one of said grooves to a position where said part can enter the other groove, and a shiftable member disposed about said sleeve and having an opening to receive said locking part when the latter and saidsleeve are moved-from one position to the other, said shiftable member be- 3. In a transmission, driving and driven parts,

a pair of spaced apart members connected, respectively, at difierent ratios with one of said parts, a shiftable' member movable to two posiable member with the other part, said shiftable member being movable into engagement with either of said spaced apart members in torque.

transmitting relation, and. into an intermediate position out of torque transmitting relation with said spaced apart members, and overrunmng slipping clutch means operatively connecting said shiftable member with both of said spaced apart members when the shiftable member is'in its intermediate position.'

4. In a transmission, driving and driven parts, a pair of spaced apart members connected, re-

spectively, to drive said driven part at different speeds, a shiftable member operatively connected. with said driving part and movable into engagement with either of said driving members and ,tions, means operatively connecting said shiftintoan intermediate position therebetween,-

manual means for moving said shiftable member from a position engaging one, of said driving members to a position engaging the ,other driving member, a pair of overrunning slipping clutch units separately connecting said shiftable member with said driving members, respectively, one of said units connecting the shiftable member with one 0 id driving members when the shiftr is inone position and the other unit connecting the shiftable member with the her is in' its other position, whereby one or the other of the overrunning clutch units is free to accommodate reverse rotationwhen the shiftab emember is in either of Its positions.

' other driving member when the shittable mem- I with said driving part and movable into engagement with either of said driving members and into an intermediate position therebetween, overrunning slipping clutch means operatively coni f necting said shiftable member with said driving members whenthe shiftable member is in its intermediate position, and manually controlled means for shifting said movable member from a position engaging one of said driving members to -a position eng ng the other driving member.

ing movable into positions preventing the pasage "of said part out of either of said grooves through said opening.

7. In a transmission, a driving member having a pair of peripheral grooves therein, a looking part adapted to bedisposed in either of said grooves, a shiftable sleeve surrounding said grooved member and having an opening in which said part is disposed and through which said part is movable to permit the part being disengaged from one of said grooves and the sleeve shifted "to a position in which the part can enter the other groove, and manually controlled means surrounding said sleeve and having an interior recess permitting the part to move out of one of said grooves and'move with said sleeve relative to said member into its other position, said looking member being shiftable in either direction from its central position for holding said part in one of said grooves to thereby lock the sleeve to said member. r

8. In a transmission, a member having helical splines, a sleeve surrounding said member and having a cooperating set of helical splines whereby said sleeve'rotates with said member, at least one of the splines of said sleeve being interrupted to form a pair of notches, and a spring biased plunger carried by said member and adapted to move in an outward direction under the action of the biasing spring and of centrifugal force so as to enter either of said recesses when the torque transmitted between said member and said sleeve causes the latter to shift in one direction or the other relative thereto.

9. In a transmission having a reverse gear and shift means therefor, aligned driving and driven shafts. a shiftable member having a torque responsive connection with said driving shaft and movable from one position to another relative to said driven shaft, a part fixed directly to said driven shaft, a second part operatively connected to said driven shaft through a set of gearing, said shiftable member being engageable with either of said parts to transmit the drive to said driven shaft either directly or through said set of gearing, means having splined connection with said shiftable member, and a pair of overrunning friction slippage clutch units separately connectin said means to said first and second parts, either of said units being capable not transmitting a limited amount of torque suflicient to move said shiftable member when the latter is out of enagement with both of said 'first and second men-; tioned parts.

10. In a transmission, driving and driven parts,

a pair of driving members connected, respectively, 1

to drive said driven par'tat difierent speeds, a shiftable member operatively connected with said driving part and movable into engagement with either of said driving members and into an inter-,- mediate position out of engagement therewith, a sleeve section disposed about each ofsaid driving members, overrunning clutch means connecting each of said sleeve sections to the associated driving member, torque-responsive means for shifting said sleeve from-one position to another, and clutch teeth formed on said sleeve sections and said shiftable member whereby, when said shiftable member is in one of its positions, one of said sleeve sections is connected to said shiftable member and, in turn, connects the latter to the associated driving member while the other sleeve section is capable of free rotation, the latter serving to connect the shiftable member, when it moves out of said one position, with the other driving member and act through said torque-responsive means for continuing the movement of said shiftable member into its other position and releasing said first-mentioned sleeve section.

11. A transmission comprising driving and driven shafts, a gear on said driving shaft, a countershaft connected to be driven from said gear, a gear member mounted for rotation on said driven shaft, means for optionally connecting said rotatable gear to be driven from said countershaft, a hub member fixed to the forward end of the driven shaft in a position between said rotatable gear and said countershaft driving gear, a shiftable member having a splined torque responsive connection with said hub member, said torque-responsive connection providing for movement of said shiftable member either-into engagement with the rotatable gear or into engagement with the countershaft driving gear, according .to torque conditions, reverse gearing rearwardly of said gears and adapted to be connected when said rotatable gear is out of connection with said countershaft gear, andoverrunning clutch units operatively connecting said shiftable member with said countershaft driving gear and said rotatable gear, respectively, said overrunning clutch means being adapted .to acconmiodatef-orward rotation of the shafts but arranged to prevent backward rotation of said driving and driven shafts when said countershaft gear is operatively connected with said rotatable gear.

12. In a driving axle construction includinga pinion shaft, and a propeller shaft, a change speed unit including an axially shif table part having torque responsive connection with-one of said shafts, change speed gearing connected to the other shaft and including one part directly fixed to said other shaft and another part in driving relation with respect to said other shaft through the change speed gearing, said aidally shiftable member being adapted to engage one or the other of said pants, and overrunning clutch means connecting said axially shiftable member with both of said parts when the shiftable member is out of engagement with both of said parts.

13. In a dri i g axle construction having a 14. In a driving axle construction having a pinion shaft and a propeller shaft aligned therewith, a change speed unit comprising a shiftable member'having a torque responsive connection with said propeller shaft and movable from one position to another relative thereto, a part fixed directly to said pinion shaft, a second part operatively connected to said pinion shaft through a set of gearing, said son-table member being engagea'ble with either of said parts to transmit the drive to said pinion shaft either directly or through said set of gearing, means having splined connection with said shif-table member, and a pair of overrunning clutch units separately connecting said means to said first and second parts when said shiftable member is out of engagement with both of said first and second mentioned parts.

15. In a transmission, a pair of members having a splined connection providing for rotation of said members together but permitting one to shift generally axially relative to the other, one of said members having a pair of recesses therein and the other member having an opening therein, a. locking part disposed in said opening and adapted .to extend partially into one or the other of said recesses according to the axial position of said one member relative to the other, said locking part and said recesses being so arranged that substantially all torque transmitted through said splined connection independently of said locking part and recesses, said part being adapted to extend outwardly of said opening when said "one member moves from one position to another relative to the other member, a locking member disposed adjacent said pair of members and having an interior recess receiving said part when said one member is moved from one position to the other with said locking member in its intermediate position, yielding means for t moving said locking member in either direction from said intermediate position, said movement pinion shaft and a propeller shaft aligned there-',

with, a change speed unit comprising a shi'ftable member having a torque responsive connection with said pinion shaft and movable from one position .to another relative thereto, a part fixed directly to said propeller shaft, a second part operatively connected to said propeller shaft through a set of gearing, said shiftable member being engageable with either of said parts to transmit the drive to said pinion shaft from said propeller shaft either directly or through said set of gearing,.means having splined connection with said shiftablemember, and a pair of over-running clutch units separately connecting said means to said first and second parts when said shiftable member is out of engagement with both of said first and second parts.

serving to lock said. part in one of said recesses if said sleeve is already in a position disposing said part in said recess, and said yielding means permitting said locking member to move temporarily beyond either of its positions when said shiftable member is moved into a correspondin position from its other position, said lockin member then engaging the locking part and holding said shiftable' member against subsequent movement.

16. In a transmission, driving and driven parts, a pair. of spaced apart members connected, respectively, to be driven from said driving part at different speeds, a shiftable member operatively connected with said driven part and movable into engagement with either of said driving members and'into an intermediate position therebetween, means for moving said shiftable member from a position engaging one of said driving members'to a position engaging the other driving member, a pair of overrunning friction slippage clutch units separately connecting said shiftable mem connecting the shiftable member with the other driving member when'the shiftable member is in its other position, whereby one or the other of the over-running clutch units is free to accommodate reverse rotation when the shiftable membe: is in either of its positions.

17. In a transmission, driving and driven parts.

1 4 a pair of spaced apart members connected, respectively, .to be driven from said driving part at difierent speeds, a shiftable member operatively connected with said driven part and movable into engagement with either of said driving members and into an intermediate position therebetween, overrunning friction slipp e clutch means operatively connecting said shiftable member with is in its intermediate position, and manually controlled means for shifting said movable member K from a position engaging one of said driving members to a position engaging the other driving member.

-18. A transmission com-prising driving and" driven shafts, a countershaft connected to be driven from said driving shaft, a gear member mounted for rotation on said driven shaft, means for optionally connecting said rotatable gear to bev driven from said counters'haft, a shiftable member having a' torque responsive connection with. said driven shaft. means for shifting-- said shifting member into engagement with the driving shaft or with said rotatable gear, and means movable in one direction from a generally central position for locking said shittable member in one of its positions and movable in the other direction for lock-' ing the shit-table member in its other position;

19. In a transmission, driving and driven parts,

a pair of spaced apart members connected with the driving part, one of said members being connected directly to said driving part and the other connected through gear means for rotation there-.

with at a different ratio, whereby one of said members normally rotates at a lower speed thanarate overrunnlng clutch means operatively connecting said shiftable member withv the slower rotating one of said spaced apart members,

whereby said driven part cannot run slower than said slower rotating member.

20. In a transmission, driving and driven parts, a pair of spaced apart members, one connected directly to said driven part and the other connected through gear means with the driven part, whereby said members rotate at difieren-t speeds relative toeach other, one of said members rotating at a lower speed than the other, shiftahle means operatively connected with said driven part'and arranged 1- engage optionally one or the other of said spaced apart members, overrunning clutch means disposed between said shiftable member and the slower rotating one of said spaced apart. members and arranged'so that said driving part cannot rotate slower than the slower rotating one of said spaced apart members, separate overrunning clutch means disposed between said shifftable member and the other of said spaced apart members, whereby said driving partpannot rotate faster than .the faster rotating" one of said spaced apart members.

21. In a transmission, a pair of driving and driven parts, spaced apart members operatively connected to drive the driven part at two different ratios, an'intermediate member having an overrunning clutch connection with each of said said driving members when the shiftable member ber, means on said shiftable member adapted to engage either of said spaced apart members for transmitting the drive from the driving part to the driven part at either of the available ratios, yielding means tending to hold said shiftable member in "either of its .positions until the amount of torque transmitted causes said shiftable member to move out of engagement with the associated one of the spaced apart members, the overrunning clutch connection between the shiftable member and the spaced apart members serving to cause said shiftable member to com- .plete its movement from an intermediate'position, in which no torque is transmitted and hence no tendency to cause the shiftabie member to be moved in eitherdirec'tion, to one of its end posi- ,tions.

22. The combination with a transmission, of a unit comprising a. driving part connected to be a driven by said transmission, a driven part, a collar fixed to one end of one of said parts adjacent the other part, an epicyclic gear unit operatively connected with said one part in driving relation and including a collar disposed adjacent said first collar, a member having a helically splined connection with said other part and shiftable axially relative thereto, whereby the transmitted torque tends to shift said member in one direction or the other according to the direction in which the torque is exerted, means yieldingly restraining said member from axial movement until the amount of torque exerted exceeds a predetermined value, and means on said shiftable memher for engaging one or the other of said collars whereby said one part may be driven fromthe other directly or through said epicyclic gear unit,

' according to torque conditions.

23. In a transmission, means providing two different ratios, a shiftable part for engaging shiftable part being shiftable from one ratio to,

the other when said retaining means is in a third position, said locking mechanism being construpted and arranged so as to be releasable while torque is being transmitted through said transmission.

24. A change speed unit comprising a pair of driving and driven parts, spaced apart members associated with one of said parts and adapted to transmit the drive to the driven part at either of two difierent ratios, an intermediate member having an overrunning clutch connection with each of said spaced apart members wherebysaid intermediate member can overrun one of'said spaced apart members and is overrun by thev other of said spaced apart members, and a movable member having an axially shiftable connection with the other part and with said inter- 

